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<head>
    <meta charset="UTF-8">
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    <title>Document</title>
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<body>
    <script>
// 编写函数，判断一个字符串的内容是不是纯数字
function fn(){
    var str="as";
if(str %1 ==0){
console.log("纯数字");
}
else {
console.log("不是纯数字");
}
}fn();

    </script>
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